The present invention relates to an obturating arrangement for the breech end of a barrel of a gun having a wedge type breechblock. More particularly the present invention relates to a base ring provided with a right-angled obturating ring having a first arm, which extends parallel to the longitudinal axis of the gun barrel, and thus of the base ring, projecting into a recess delimited by a bead of the base ring and, in order to provide obturation, having its exterior face lying against the outer axially extending abutment surface of the recess, and having a second arm, which is arranged at a right angle to the gun barrel and to the first arm, extending radially inwardly beyond said bead so that its exterior surface can lie against an insert of a breechblock wedge to provide obturation.
Such an obturating ring arrangement is disclosed in the book, entitled "Handbook on Weaponry", published by Rheinmetall GmbH, Dusseldorf, 2nd English Edition, 1982, page 340, FIG. 862.
The arm of this obturating ring which projects into a recess in the base ring is axially supported at the base surface of the recess. The bottom of the base ring is difficult to clean, and thus sometimes it is possibly insufficiently cleaned so that the powder residue generated by the firing of a round and deposited at the bottom of the base ring may creep underneath the supporting face of the arm and, in a disadvantageous manner, reduce the basic play of the obturating ring relative to the breechblock wedge. This can possibly compress the breechblock wedge before it reaches its final position and prevent it from performing a complete closing stroke.